Field bus system, comprising (i) at least one field bus module with a connection unit for the connection to a network, wherein a control unit can be connected to the network and the at least one field bus module can be addressed in the network, and with a plurality of ports for the connection of field devices, in particular sensors and/or actuators, and (ii) at least one address connector which has a non-volatile memory for an address, wherein the at least one field bus module has an address port for the at least one address connector and the address of the at least one address connector in the network is communicated to the field bus module via its connection.